3-demethylthiocolchicine has broad-spectrum antitumor properties and has been reported to inhibit migration of amyloids (A. Brossi et al, Med. Res. Reviews. 1988, Vol. 8, pp. 77-94). Therefore, 3-demethylthiocolchicine is a substitute of colchicine having an improved therapeutic index. Although 3-demethylthiocolchicine is a known compound, the ester derivatives thereof having similar biological properties have not been reported.
U.S. Pat. No. 4,692,463 by Brossi, which is not prior art against the instant invention, describes the finding of potent antiinflammatory properties in 2,3-didemethylcolchicine and its derivatives. Although 3-demethylthiocolchicine is disclosed, the esters thereof are not reported. The contents of this patent are herein incorporated by reference.
U.S. Pat. No. 3,997,506 by Dugat discloses anti-mitotic and anti-gout derivatives of thiocolchicine.
U.S. Pat. No. 3,816,396 discloses a process for the preparation of glucoside derivatives of thiocolchicine.
U.S. Pat. No. 2,820,029 by Muller et al discloses thio-derivatives of colchiceine compounds and a process of making the same.
A publication by Kerekes et al entitled "Esters of 1-0-Demethylthiocolchicines: Formation of Isomers in Chloroform Solution", Helvetica Chimica Acta. Vol. 68, 1985, p. 579, discloses 3-0-Acetyl-10-demethoxy-3-0-demethyl-10(methylthio) colchicine.
A French language publication by Velluz et al entitled "La thiocolchicine. III. - Etude de quelques S-alcoyl-thiocolchiceines", Memoires presentes a la Societe Chimique, pp. 194-197, discloses the preparation and study of thiocolchicine.